Hopper feed for carton blanks



April 28, 1964 J. LE BRELL HOPPER FEED FOR CARTON BLANKS 2 Sheets-Sheet1 Filed Dec. 21, 1961 mum/r02. (/MN 45 3,6514 J e panda/M439 April 28,1964 J. LE BRELL HOPPER FEED FOR CARTON BLANKS 2 Sheets-Sheet 2 FiledDec. 21, 1961 hwavme: (fa/{Iv 4/5 51861: W pw/mm4 United States Patent3,130,967 HGPPER FEED FOR CARTGN BLANKS 501m Le Brell, Hermann, Mm,assignor to Alton Box Board Company, Alton, 111., a corporation ofDelaware Fiied Dec. 21, 1961, Ser. No. 161,129 8 Claims. (Cl. 271-62)This disclosure relates generally to machines for setting up foldingcartons, and is particularly addressed to the portion of a machine whichholds a supply of unfolded blanks.

It is common practice to manufacture cartons from precut and scoredblanks of paperboard or similar material. The unfolded blanks areconveniently shipped and stored in stacks, and a machine is commonlyemployed to fold the blanks into finished cartons at the point of use.Many such machines incorporate a magazine, hopper or other device forholding a supply of unfolded blanks, which are fed automatically to thefolding mechanism. Customarily, the blanks are arranged in a stack withthe machine drawing single blanks from one end and a machine tender orworker replenishing the supply from time to time, by adding blanks ingroups to the other end of the stack.

A common arrangement is to provide inclined rails with the blanks ridingat their lower edges on the rails and a heavy back-up weight also ridingon the rails to maintain pressure on the back of the stack and move thestack forwardly as individual blanks are pulled by the machine from thefront of the stack. The weight is pulled back when a group of blanks isto be added to the supply. The heavy weight type of blank feed avoidscertain problems encountered with positive blank feeds, but does presenta problem in providing sufficient forward force without becoming awkwardto manipulate when the machine tender adds to the supply. Accordingly,an

object of this disclosure is to provide an improved feed system forstacked blanks in a carton set-up machine, and more particularly toprovide a system in which the forward thrust on the blanks is, in part,independent of the weight of the back up member or angle of the rails,which hold the stacked blanks. In addition, the disclosure provides asystem particularly useful in handling waxcoated blanks, such as thoseused in packaging frozen foods, since wax tends to accumulate upon guiderails and interfere with operation.

In the attainment of these objectives, briefly, the mechanism hereindisclosed comprises bottom rails and side rails which engage the bottomand side edges of a stack of blanks. The rails are in the form of rods,which are rotated continuously in predetermined directions. The bottomrods are rotated in opposite directions, so as to offset side thrust andthe side rods may produce a downward thrust.

The surfaces of the lower rods are roughened in a spiral pattern, as bymoving emery cloth down a rod as it is rotated in a lathe. This spiralgrain acts upon the blanks much like a screw or thread to move theblanks along the rods, but the grain is slight, so that there can berelative motion between the blanks and rotating rods. Accordingly, theblanks are fed in the hopper by a frictional screw drive. A back-upmember is employed to hold the blanks upright, and it is supported bywheels riding upon the rods. Some of these wheels are freely journalledwith their axes crosswise of the rods, so as to rotate with the rods,and their effect is to permit or cause a slow forward progression of theback-up member along the rod. Accordingly, when the back-up member ispulled back from the blanks and released, it does not immediately slideback down against the blanks. Rather, there is a slow forward advance,which permits one to insert additional blanks without holding theback-up member away from the blanks already in the hopper. In thissense, the wheels act as a slipping brake, which automatically controlsthe movement of the back-up member during loading of the hopper.

The rate of advance of the blanks is determined by the spiral of thedriving rods and their speed of rotation. The rate of advance of theback-up member may funther be determined by setting the wheels withtheir axes at a slight angle relative to the axes of the rods.

Other features of the invention will be in pant apparent from and inpart pointed out in the following detailed description taken inconnection with the accompanying drawings, in which:

In FIG. 1 is a side elevation illustrating a hopper embodying featuresdisclosed herein;

FIG. 2 is a top plan view of the hopper;

FIG. 3 is a section taken on the line 3-3 of FIG. 1;

FIG. 4 is a section taken on the line 44 of FIG. 1; and a FIG. 5 is asection taken on the line 5-5 of FIG. 1.

Referring to the drawings, there is shown a hopper or magazine forcarton blanks B carried in an inclined stack. The blanks are supportedat their lower edges upon a pair of parallel inclined rods 1 and areretained against lateral displacement by a second pair of parallel rods3 disposed above and outwardly of the rods 1. The rods are journalled attheir ends in a front header 5 and a back header 7, the arrangementbeing one wherein the rods slope downwardly to the front.

The blanks collect at the front of the unit and are held upright in astack by a back-up member of follower 9, which is movable over the rods.An individual blank is drawn from the front of the hopper, as by asuction cup C or set of cups, and is carried thereby to a foldingmechanism, such as a plunger and die (not shown).

It will be understood that this magazine forms part of a larger machinefor automatically forming blanks into cartons and such machines operateat high speeds. As the blanks are withdrawn individually, the stackmoves forwardly. Intermittently, the supply of blanks is replenished bypulling back the follower and manually inserting additional blanksbehind those already in the magazine. This disclosure is particularlyconcerned with the problems of simplifying the reloading operation andfeeding the blanks forwardly on the rods.

More particularly, the lower rods 1 have collars 11 secured to theirforward ends, and the collars act as stops limiting the forward movementof the stacked blanks.

A front framework 13 also carries stop fingers 15 at the sides of thefront blank and an upper guide and stop assembly 17 The suction cup isadapted topull the lower part of the front blank over the collars 11 andthen pull the entire blank downwardly clear of the stop fingers 15 'andassembly 17, the blank being then moved to the folding or formingmechanism. These details are not significant to the present disclosure,hence are not further described.

The rods are otherwise journalled and project through bearings 19fastened to the back header 7. The projecting end of each rod carries asheave, there being sheaves 51 and 52 on the lower rods 1 and sheaves 53and 54 on the outer rods 3 (FIG. 5). A driving belt 21 is trained aboutthe sheaves 51, 52, S3, 54, and this belt also passes about idlersheaves 55 and 56 and a drive sheave (not shown). It may be noted thebelt passes over sheave 53, under sheave 51, over sheave 52 and thenceunder and about sheave 54, so that the two lower rods 1 are driven inopposite direction and so that the two upper rods 3 are likewise drivenin opposite directions. As indicated by the arrows of FIG. 5, thedirections of rotation are such that the outer rods 3 tend to exert aslight downward thrust on the blanks at their side edges, whereas theside thrust of one lower rod counteracts that of the other lower rod.However, the outer rods might be driven in such a way as to exert alifting force on the blanks.

The rods are rotated continuously, and this is desirable in'feedingwaxed blanks, since there is then a minimum of wax build up on'the rods,such as would interfere with the feeding of the blanks. Also, therotation of the rods is herein utilized to produce .a forward feedingforce on the blanks. This is accomplished by giving the lower rods aslight surface roughening in a helical or screw-like pattern. The degreeof roughening is that obtained when a piece of emery cloth is pressedagainst a rod and moved longitudinally while the rod is rotated in alathe. This roughening is to be distinguished from a true thread orscrew because a slipping or frictional drive, rather than positive driveis desired. The'forward feed should necessarily be sufiicient tocompensate for the withdrawal of blanks by the suction cup, and willdepend upon the pitch of the grained surface and thespeed of rotation.The latter may be varied, but preferably is proportional to the rate atwhich blanks are withdrawn and the rate at which cartons are formed. Inother words, the belt 21 would be driven in synchronism Withthe othermechanism of the machine.

With the blanks being fed by the rods, the forward force exerted by thefollower 9 need not be nearly as great as would be necessary were thefollower to supply all of the blank feeding force. Indeed, the followermerely serves to hold the blanks upright at the back of the stack, theblanks at the front of the stack'being held upright by the parts 15 and17.

Moreover, the follower is supported so that it tends to move forwardlyat a rather slow speed, not much greater than the rate of blank advanceand much slower than would be the case were it free to roll orslidefreely down the rods. When the follower advances slowly, it may notbe necessary to hold it back while replenishing the supply-in a sense,the follower holds itself back for a delayed interval. Even if it isnecessary to hold the follower, only a light force is required.

The follower is carried by four rollers 23, two at each side, over theouter rods 3. .A lower roller 25 is disposed below .each rod 3 betweenthe two upper rollers 23 for that rod. The rollers 25 have their axesperpendicular to the axes of the rods, whereas the rollers 23 arejournalled with their axes approximately (but not exactly parallel tothe rods. Otherwise, the follower is retained agianst lateraldisplacement by nylon discs 27 between the lower rods 1. These discs maybe fixed by bolts, which are eccentric with respect to the periphery ofthe discs, so that the angular adjustment of thediscs will take up anyslack.

When the rods are rotating, the follower is carried by the rollers 23,which rotate with the rods. The rollers 25 are used only to keep thefollower from coming off the rods when it is pulled back. The rollers 23prevent the follower from rolling down the rods. Rather, the rollers 23control the rate of forward advance. This rate of advance can, in turn,be controlled by disposing the roller with their axes at a slight angle(say from'true parallel with respect to the rods. The arrangement is oneassuring a forward advance of the follower, but at slow rate. The actualrate of advance may depend in part upon other factors, such as inclineof the rods and weight of the follower.

It is not practical to give exact relationships, but they can be readilyworked out for a given machine in the light of this disclousre. Indeed,it will be apparent, the unit might be made with the rods horizontal,although some incline is helpful in keeping the blanks upright when thefollower is pulled back.

Other variations and modifications will, no doubt, occur to thoseskilled in the art, without departing from the spirit of the disclosure,or scope of the claims.

Having thus described the invention, what is claimed and desired to besecured by Letters Patent is:

l. A hopper for carton blanks to be fed to a forming machine, the hopperhaving a first pair of rods upon which a stack of carton blanks issupported with the cartons resting on the rods at their lower edges, asecond pair of rods extending generally parallel to and above andoutwardly of said first rods in positions such that they may be engagedby the side edges of the blanks, said rods being journalled for rotationabout their axes, means rotating each of said rods, and a followercarried by one of said pairs of rods, said one pair of rods beingrotated continuously in opposite directions, and means forming afriction drive connection between said follower and its supporting rodsfor moving the follower therealong at a rate proportional to therotational speed of the rods when the follower is not otherwiserestrained, said friction drive permitting the follower to be pulledback from the stack of blanks and its rate of movement beingsufiiciently slow to permit the follower to be released and a supply ofblanks added to the stack before the follower returns to the stack ofblanks.

2. A hopper for carton blanks to be fed to a forming machine, the hopperhaving means supporting a stack of blanks on their edges, friction feedmeans cooperating with the blanks to advance the stack toward one end ofthe hopper, a follower normally engaging the stack of blanks at itsother end but retractable therefrom, friction feed means moving saidfollower in the same direction as the blanks, said blank feed meansfunctioning independently of said follower, so that the blanks are fedeven when the follower is retracted from the stack of blanks, and saidfollower feed means having a rate of advance slightly faster than thatof said blank feed means.

.3. In apparatus for feeding articles in a predetermined direction, theimprovement that comprises a cylindric rod mounted for rotation aboutits axis and disposed with its axis extending generally in saidpredetermined direction of feed with its surface in contact with saidarticles, means for rotating said rod, the surface of said rod beingessentially smooth and free of threads and flights but for a pluralityof fine scratches in a substantially helical pattern, said scratchesbeing of a character produced by an abrading medium moved along the rodwhile it is turned, thereby to produce a surface which permitslongitudinal slip between article and rod yet moves the article alongthe rod when the rod is rotated and the article is free of restraint.

4. In apparatus for feeding articles in a predetermined direction, theimprovement that comprses a cylindric rod mounted for rotation about itsaxis and disposed with its axis extending generally in saidpredetermined direction of feed, means for rotating said rod, an articlefollowermounted for movement along said rod, a wheel journalled in saidfollower in riding engagement with said rod, said wheel being disposedwith its axis lying at an acute angle relative to the axis of said rod,whereby rotation of the rod causes rotation of the wheel and .the angleddisposition of the rotating wheel moves the follower along the rod at apredetermined rate proportional to the speed of rotation of the rod andthe angle of the wheel axis to the rod axis.

5. In a hopper for feeding carton blanks to a forming machine, theimprovement that comprises a plurality of rods mounted for rotationabout their axes and disposed to sustain a stack of carton blanks attheir edges, means for rotating said rods, at least one of said rodshaving a cylindric surface free of threads and flights but for aplurality of fine scratches in a substantially helical pattern, wherebysaid rod will move the blanks along the rod when the rod is rotated andthe blanks are free of restraint yet permit restraint of the blankswithout damage thereto while the rod is rotating.

6. In a hopper for feeding carton blanks to a forming machine, theimprovement that comprises a plurality of rods mounted for rotationabout their axes and disposed to engage a stack of carton blanks attheir edges, a follower mounted for movement along said rods inengagement with the stack of blanks, a Wheel journalled on said followerin riding engagement with one of said rods, means for rotating said rodabout its axis, said wheel being disposed with its axis lying at anacute angle relative to the axis of said rod, whereby rotation of therod causes rotation of the rotating wheel and the angled dis position ofthe wheel moves the follower along the rod.

7. Apparatus for biasing a stack of sheets toward one end of apredetermined path which is substantially parallel \m'th the thinnestdimension of the sheets, comprising a rod whose surface is substantiallycylindrical, whose axis is substantially parallel with said path, saidrod being arranged to sustain a substantial part of the weight of atleast some of the sheets in said stack, the substantially cylindricalsurface of said rod having a multiplicity of 6 scratches extending at anacute angle with an intersecting plane which is normal to the axis ofthe rod, and means for driving said rod in rotation about its axis.

8. The apparatus of claim 7 wherein there are two such rods spacedradially from each other and each engages the same edge of a sheet, saidrods having their surface scratches reversely oriented and theirdirection of rotation opposite.

References Cited in the file of this patent UNITED STATES PATENTS1,564,926 Armstrong et al. Dec. 8, 1925 1,971,574 Moon Aug. 28, 19342,193,942 Shackleford Mar. 19, 1940 2,642,285 Baker et al. June 16, 19532,869,715 Williams Jan. 20, 1959 2,872,190 French Feb. 3, 1959

1. A HOPPER FOR CARTON BLANKS TO BE FED TO A FORMING MACHINE, THE HOPPERHAVING A FIRST PAIR OF RODS UPON WHICH A STACK OF CARTON BLANKS ISSUPPORTED WITH THE CARTONS RESTING ON THE RODS AT THEIR LOWER EDGES, ASECOND PAIR OF RODS EXTENDING GENERALLY PARALLEL TO AND ABOVE ANDOUTWARDLY OF SAID FIRST RODS IN POSITIONS SUCH THAT THEY MAY BE ENGAGEDBY THE SIDE EDGES OF THE BLANKS, SAID RODS BEING JOURNALLED FOR ROTATIONABOUT THEIR AXES, MEANS ROTATING EACH OF SAID RODS, AND A FOLLOWERCARRIED BY ONE OF SAID PAIRS OF RODS, SAID ONE PAIR OF RODS BEINGROTATED CONTINUOUSLY IN OPPOSITE DIRECTIONS, AND MEANS FORMING AFRICTION DRIVE CONNECTION BETWEEN SAID FOLLOWER AND ITS SUPPORTING RODSFOR MOVING THE FOLLOWER THEREALONG AT A RATE PROPORTIONAL TO THEROTATIONAL SPEED OF THE RODS WHEN THE FOLLOWER IS NOT OTHERWISERESTRAINED, SAID FRICTION DRIVE PERMITTING THE FOLLOWER TO BE PULLEDBACK FROM THE STACK OF BLANKS AND ITS RATE OF MOVEMENT BEINGSUFFICIENTLY SLOW TO PERMIT THE FOLLOWER TO BE RELEASED AND A SUPPLY OFBLANKS ADDED TO THE STACK BEFORE THE FOLLOWER RETURNS TO THE STACK OFBLANKS.